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Altera_Forum
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14 years ago

Unused CPLD Pins

I have two CPLDs on my PCB that connect to a common SPI bus. In order to keep things simple I'm trying to talk to only one of the chips at first but I'm having some trouble with the voltages which le...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

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Which device are you using?

The setting is under:

Assignments->Device, Device and Pin Options button, Unused Pins

(which can be a tab or selection menu depending on Quartus version).

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Yep. Just changed it and the warning disappeared. The devices are Max V 5M240ZT100.

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Yep.

Its a stupid default, which has been changed to a sane value for newer devices.

This is why I always define a top-level entity with every signal pin defined. Then the unused pins really are unused and the unused pin setting is of no consequence.

Cheers,

Dave

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I don't know why it was set to the older default then. I'm 100% sure I did not change this setting and always remember seeing the warning in the compilation log.